A nine-year veteran in MLS, Riley has made a total of 211 appearances for a total of five clubs. Riley spent the 2013 season with D.C. United, making 21 appearances in league play while helping the team win the 2013 U.S. Open Cup, but was released by the team through the league's Re-Entry Draft process. The defender has also made stops with the New England Revolution, San Jose Earthquakes, Seattle Sounders FC, and Chivas USA